Resistor terminal cutter



' Oct. 22, 1957 w. A. RINEHART RESISTOR TERMINAL CUTTER Filed June 12, 1957 Z. R. A R E m w United States Patent RESISTOR TERMINAL CUTTER Walter A. Rinehart, Newark, N. J. Application June 12, 1957, Serial No. 665,273

2 Claims. (Cl. 30-124) The invention relates in general to cutlery, and has particular reference to an implement devised for the exelusive purpose of cutting the terminal connector wires of resistors while installed in electrical apparatus.

Resistors, which are included among the more numerous electrical components of the operational circuits of radio and television sets and of other electrical apparatus such as telephone switchboards, usually are installed with the ends thereof that carry the terminal connector wires facing inward so as to be invisible to a maintenance repairman and diflicult of access when it becomes necessary to sever the terminal wires to permit removal of any of the resistors. Also, to the difficulty of gaining access to the terminals of an installed resistor is added the practical inability of the repairman to seize and hold the resistor following detachment. Due to the trend toward miniaturization of electrical circuit components, resistors in particular have become dwarfed in comparison with the hand implement customarily employed in cutting the terminal wires, such as a pair of side-cutter pliers. Consequently, any resistor that is to be detached is likely to be completely masked by the conventional cutting implement heretofore employed and cannot be grasped by the repairmans free hand to prevent it from falling after the terminals are severed.

It therefore is the primary object of my present invention to provide a special cutting implement that has sufliciently attenuated jaws to permit easy insertion into the greatly restn'cted spaces surrounding an installed resistor, and that will include the latter in their embrace and grip at the instant of complete severance of the concealed terminals.

To be more explicit, all dimensions of the jaws of my special implement correspond to the external form and size of a standard resistor and thereby facilitate rapid and accurate application to an installed resistor, even though the latter cannot be seen in its engaged position. As a re sult, when the implement is withdrawn, the detached resistor will come out with it in securely gripped condition.

Other objects, advantages and features of the invention will become apparent as the following specific-description is read in connection with the accompanying drawing, in which:

Fig. l is a large-scale side elevation of the implement during the act of engaging an installed resistor, parts of the implement and resistor-including electrical apparatus being shown broken away; Fig. 2 is a similar view, showing the resistor safely gripped between the jaws of the implement following severance of the terminals; and Fig. 3 is a transverse section of the implement jaws and held resistor on line 3-3 of Fig. 2.

Referring now in detail to the drawing, wherein like reference characters designate corresponding parts in the several views, Figs. 2 and 3 in particular disclose the cooperatively related dimensional proportions of the special implement and the electrical resistor which it is intended to serve.

Resistor R has a body b of standard cylindrical form and size and the usual pair of axially projecting terminal connector wires t-t at one end in electrical connection with the built-in resistive conductor (not shown).

The special resistor terminal cutter comprises articulated cross-handles 10 and 11 that are pivotally united preferably by a medial pivot pin 12 and support coacting jaws 13 and 14 of special design on the ends thereof opposite to manipulating portions 15 and 16. Jaws 13 and 14 include the respective side members 17 and 18 and the inwardly presented cutter blades 19 and 20 that are in positions to be forced into mutual registering contact when the manipulating portions 15-16 of handles 10-11 are pressed inwardly toward each other. I

The transverse length of cutter blades 19-20 is slightly greater than the distance which separates terminal connector wires t-t of the co-related resistor R and the degree of inward projection of cutter blades 19 and 20 from the supporting side members 17 and 18 is equal to half the outside diameter of resistor body b. The matching dimensional relation of implement jaws to resistor body is pursued further by making the length of side members 17-18 equal to the length of resistor body b. Moreover, the relative angular arrangement of side members 17-18 inust be such that, when the jaws 13 and 14 are closed with cutter blades 19-20 in mutual contact, the said side members will be parallel and spaced apart just sufliciently to contact and tightly grip an embraced resistor body b throughout its length.

In the operational use of my special implement to cut the terminals of an installed resistor, it should be entirely practicable to insert the attenuated jaws 13-14 into a space in the electrical apparatus A in which the resistor is installed directly alongside the body b of the latter. Then, when cutter blades 19-20 bear against the concealed inner end of resistor body b, which can be felt even if not seen, the implement may be slid sideward, while the jaws are partially open, to bring body b of resistor R in between side members 17-18 so as to be embraced thereby. In this partially open-jawed condition of the implement, the inner edges of cutter blades 19-20 will clear terminals t-t during sideward movement of the jaws. Thereafter, inward manipulation of handles 10-11 of the implement will cause cutter blades 19-20 to sever terminals t-t, and resistor body b will become tightly gripped between side members 17-18 so that it may be withdrawn instead of being accidentally dropped on the floor.

It will be understood'that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purpose of illustration which do not constitute departures from the spirit of the invention and scope of the appended claims.

I claim:

1. A terminal cutter for cooperative use in connection with an installed electric resistor of standard length and diametrical width comprising: a pair of articulated crosshandles united by intermediate pivot means; and a pair of jaws supported by said handles, each of said jaws including an attenuated side member and a substantially perpendicular inwardly presented cutting blade at the free end thereof, the respective lengths of both side members of the jaws being substantially equal to the length of the resistor to be served and the inward extent of the respective cutting blades being substantially equal to one-half the diameter of said resistor.

2. A terminal cutter as defined in claim 1, wherein the relative angular arrangement of the respective jaws is such that the inner faces of the side members thereof will be parallel and separated by a distance substantially equal to the diametrical width of the resistor to be served, whereby the latter will be gripped between said side members, when the cutting blades have come into mutual contact during severance of the resistor terminals.

No references cited. 

